1. Field of the Invention
The present invention relates in general to a seat slide device for sliding a seat to a desired position to provide a seat occupant with a comfortable sitting posture, and more particularly, the present invention is concerned with a powered seat slide device which slides the seat by the aid of a motor.
2. Description of the Prior Art
Hitherto, various types of powered seat slide devices have been proposed and put into practical use particularly in the field of motor vehicles. However, due to their inherencies, some of the conventional powered seat slide devices are compelled to have unsightly gear mechanisms naked or exposed to the view thereby deteriorating the external appearances thereof. This has narrowed the industrial field where such powered seat slide devices are practically used.
One of measures for solving such drawback is disclosed in Japanese Utility Model Second Provisional Publication No. 57-47225. In this measure, the gear mechanism is substantially entirely housed in an elongate tunnel-like space defined by the coupled stationary and movable rails. Because the unsightly parts of the gear mechanism are concealed by the coupled rail unit, external appearance of the seat slide device is improved. However, mounting the almost all parts of the gear mechanism in the tunnel-like space brings about a need for increasing the size of the coupled rail unit. As is known, bulky construction of the seat slide device causes not only increase in weight but also raise the seat to such a height as not to provide a seat occupant with a comfortable sitting posture.